Real-World Experience and Outcomes With Percutaneous Coronary Intervention for Protected Versus Unprotected Left Main Coronary Artery Disease: Insights from the Veteran Affairs Clinical Assessment Reporting and Tracking Program

Abstract

Practice patterns and outcomes of protected left main (PLM) and unprotected left main (ULM) percutaneous coronary intervention (PCI) are not well defined in contemporary US clinical practice. Data collected from all Veteran Affairs (VA) catheterization laboratories participating in the Clinical Assessment Reporting and Tracking Program between 2009 and 2019. The analysis included 4,351 patients undergoing left main PCI, of which 1,306 pairs of PLM and ULM PCI were included in a propensity matched cohort. Selected temporal trends were also assessed. The primary outcome was MACE outcomes at 1-year, which was defined as a composite of all-cause mortality, rehospitalization for myocardial infarction (MI), rehospitalization for stroke or urgent revascularization. ULM PCI patients in comparison to PLM PCI were older (71.5 vs 69.2; P < 0.001), more clinically complex and more likely to present with ACS. In the propensity matched cohort, radial access was used more often for ULM PCI (21% [273] vs. 14% [185], P < 0.001), and ULM PCI was more likely to involve the LM bifurcation (22% vs 14%; P = 0.003) and require mechanical circulatory support (10% [134] vs 1% [17]; P <0.001). One-year MACE occurred more frequently with ULM PCI compared to PLM PCI (22% [289] vs. 16% [215]; P = < 0.001) and all-cause mortality was also higher (16% [213] vs. 10% [125]; P = < 0.001). In the matched cohort there was a low incidence of rehospitalization for MI (4% [48] ULM vs. 4% [48] PLM; P = 1.000) or revascularization (7% [94] ULM vs. 6% [84] PLM; P = 0.485). In this real-world experience patients undergoing PLM PCI had better one-year outcomes than those undergoing ULM PCI, but in both groups there was a high rate of mortality and MACE at one-year despite a relatively low rate of MI or revascularization.•What is known?○In contemporary practice, the use of percutaneous coronary intervention (PCI) for left main coronary artery disease has increased.○Clinical trials have demonstrated that left main PCI can be performed safely, but observational studies have shown that patients who undergo left main PCI are older and with more co-morbid conditions than trial populations.•What the study adds?○In a large multi-center sample from the United States Department of Veterans Affairs, there has been increasing use of left main PCI in patients who have not undergone prior coronary artery bypass graft surgery (CABG).○Compared to patients with prior CABG who underwent left main PCI, those who underwent left main PCI without prior CABG had a higher rate of major adverse cardiovascular events and all cause death at 12 months.○While there was an overall low rate of rehospitalization for myocardial infarction or revascularization, there was a higher 12-month incidence of major adverse cardiovascular events in this real-world population compared to clinical trial populations.